Very useful information regarding the engine on our rattlers

[Smellybumlove]

ok my brain hurts, been doing tons of research in english and chinese and this is what i have found out:

our rattlers use the SAME engine as the 100cc yamaha BWs which is a zuma btw.

it just has a longer stroke from 47.6mm to 50mm, so everything should fit including the 123cc kit which will take us to 130cc RELIABLY!.

BWs 100: 47.6x52
rattler 110: 50x52

this explains why my exhaust matched up perfectly with only a bend required to fit!.

now going to fit a keihin pwk30 carb with the BWs manifold and start with the extreme porting and 58.5mm piston

[BGK]

Connecting Rod length and the stroke difference can be quite significant in whether a cylinder will work regardless of similarities in cylinder stud placement and exhaust outlet orientation. I'm not saying that it won't work, but that port timing modifications will have to be made. Also, I recall the manifold bolt pattern between the two is different (at least on the US version) than the BWS100, which is the same as the 50. I've wanted to build a long stroke 100cc+ jog motor (very different from the BWs100 motor) but I've come to the conclusion that there are a greater number of higher end tuning parts available for the 50cc based motor. More aggressively ported and liquid cooled cylinders, performance crankshafts, internal rotor ignition systems as well as higher performing exhausts and transmission options. It will take a lot of special work to get a 110 motor to get to a legit 15+ hp, but there are many off the shelf options for the 50cc motor that are relatively bolt and giving up to 18+ hp and with more advanced tuning over 25 while remaining under 75cc. Money is about the only limiting factor between those numbers

[Smellybumlove]

hmm ok, well if the carb manifold fits and i know the exhaust fits then its safe to say it will be 100% the same.
also did you know PGO made the zuma/BWs/MBK booster (PGO make your rattlers!).

there is a 53mm crank for the BWs thats a huge 6mm difference, combine that with a 57mm piston that i know fits our bikes, that makes a 135cc monster!.

stuck on which carb to get, either a PWK28 or PWK30, im thinking the 30 as im already at 112cc and planning to go bigger.

[brimstone]

you sound like the tim taylor of scooters....you'll have to keep us posted on whether it all works out.

[Smellybumlove]

DOH and double DOH!

ok got the 28mm, its a keihin with the keihin scratched off, made in the same factory (in taiwan) but only $90 new!.
i was convinced not to go with 30mm as even at 135cc its to big for my motor .

anyway got the BWs manifold and it bolts on but leaves the carb in the wrong place, so having to have it 're-enginered' in much the same way as my exhaust .

so BWs parts do fit but dont if you know what i mean

[BGK]

That's good to know that the manifold is the same, but I'd suggest anyone stateside to check before ordering a lot of parts.

I'd not doubt that PGO made the motor for the bw100. But over the years sometimes little things change. Your's is an older model 110 isn't it?

[Smellybumlove]

yep its a 2001, they stopped making these a few years back and only make them for export.